Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly, idempotent, non-destructive behavior, so the safety profile is covered. The description usefully adds the cost (20 credits, Tier 2) and the shape of the returned content, but says nothing about determinism, location sensitivity, or the polar-latitude edge case where sunrise/sunset are undefined.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core purpose in one sentence, with zero filler and no repetition. The bracketed metadata block is rote but compact and skimmable.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 15-parameter, location-and-timezone-sensitive Vedic calculation, a one-line purpose plus metadata leaves the agent without routing guidance or parameter meaning. The presence of an output schema and annotations removes some burden, but the high parameter complexity is unaddressed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is only 33%, so the description should compensate, yet it merely restates the four required parameters already declared in the schema. It contributes nothing about ayanamsa, zodiacType, houseSystem, timezone, or precision, which materially change the Hora output.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The phrase '24 planetary hours per Chaldean order, with sunrise/sunset and day ruler' names a concrete resource and scope (the Hora division of the day) and implicitly separates it from the tithi/karana/yoga/nakshatra siblings. It lacks an explicit compute/get verb and never names a sibling, so it is clear but not maximally differentiating.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no statement of when to call this versus panchang_full, panchang_choghadia, or any other panchang tool, and no prerequisites or exclusions. The bracketed metadata gives required inputs and cost, but that is operational data, not usage guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.